Topic on Glossary talk:Central Processing Unit (CPU)
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I'm not talking about the usual just-so-frequent incompatibilities, crashes, or other obvious problems, and not even about the various hacked overclocking tools. But something a bit more in the shadow:
- Llano has quite reduced DIV/IDIV performance (I'm really not the the guy recommending to undo errata fixes, but considering all the recent guarding around speculative execution.. maybe there is a chance?)
- Bulldozer has crippled x87 performance (there are no public errata regarding the feature, so this might be all free real estate?)
- Possibly every architecture before Ryzen could hit the TDP ceiling before even reaching the maximum frequencies
(unclear whether this couldn't just be specific to some motherboards and/or workload though)
- this is probably just Turbo Core (whatever its versioning) being dynamically adjusted according to the current load. It can be fooled then, and some OEMs may actually be doing this from the firmware (Turbo CPB and Turbo Performance Boost Ratio being some likely names?). Or at least I can't explain why else the same CPU getting downclocked for clear TDP reasons would be reported elsewhere happily running dozens of watts above the official limit.
- Steamroller CPUs are throttled when their iGPU is in use (which seems a pretty common scenario for every "low budget gamer", but of course you would have to first be CPU-limited to even hope for an improvement). Alternatively if a modded BIOS isn't available, editing p-states and disabling APM should be enough.
- funnily enough, this didn't seem to happen at least on the oldest bobcat apus, and it was somewhat holding down GPU performance
And I could swear I knew more, but time was hard on my memory.
p.s. Ryzen is so complex and wide that you'd need a manual just to understand the stock situation.